Question: $ { \left[\begin{array}{r}{1} \\ {-1} \\ {3}\end{array}\right]-\left[\begin{array}{r}{1} \\ {4} \\ {2}\end{array}\right] = {?} } $
Answer: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{r}{1}-{1} \\ {-1}-{4} \\ {3}-{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{r}{0} \\ {-5} \\ {1}\end{array}\right]}$